<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<script src="js/vue.js" type="text/javascript" charset="utf-8"></script>
	</head>
	<body>
		<div id="app">
			{{a}}
		</div>
	</body>
	<script type="text/javascript">
		var data={a:1};
		var app=new Vue({
			el:'#app',
			data:data,
		});
		app.$watch('a',function(newVal,oldVal){
			console.log("from "+ oldVal +" to "+newVal);
		})
		
		data.a=2;
		app.a=3;
		console.log(data===app.$data);
		console.log(data.a===app.a);
	
		
		
	</script>
</html>
